I use MFCSFCED for all my ship modelling which doesn't do OBJ files, only MOD files. This includes making new meshes from scratch. It does the job fine, it was free and I don't like spending money unnecessarily. (I'm half Yorkshire on my mother's side).
Here's the conversion process I use. It's not meant for this purpose but neither are hammers designed to drive in screws, but you can still hammer them into wood.
I have to load and highlight the mesh for the SFC 2 model.
Copy and export it.
Load any SFC 1 model of comparable size.
Import the SFC 2 mesh copy.
Delete the original host SFC 1 model.
Highlight the imported mesh.
Move the imported mesh down to the positioning markers.
If the hard and damage points haven't been done on the original SFC 2 model, spend the time putting them in. Not everybody does the hard and damage points. Normally these carry across if they're done.
Save the new SFC 1 mesh to a new folder and file.
This gives me a playable mesh in SFC 1 at least.
Copy the skins, text file and stuff to the new folder for the SFC 1 version of the model.
Next I have to carry over the skins. Some attach automatically, some can be a pain and have to be completely attached as for a new model. It seems to depend who made the model. No trouble with Mudd's, Models Pleases's or Atrashasis' so far. Others I can spend hours with with some meshes (usually red ones) refusing to receive all the skins. One, a Gem Hadar fighter, has the main hull unskinned mesh red with the warp engines and everything else skinned just fine.
Only on models with red meshes does this occur. The funny thing is it looks fine in Model Viewer, just not in the actual SFC 1 game.
Other options are to make LOD layer versions of the new model withless detail by copying it and trimming away the polys, but only really needed on uber detailed very large models likely to be run in large ship numbers / players LAN games and on some of the slower computers here.
usually I don't bother.
Break models cannot be converted or created by MFCSFCED so I don't use them, preferring the default explosion to show that they've been destroyed in a game.